TIJUANA  Two shots that rang out 20 years ago today in Lomas Taurinas are still vivid memories in this working class neighborhood and across Mexico of the day that presidential candidate Luis Donaldo Colosio was killed.

The assassination threatened to plunge Mexico into its worst political crisis in more than six decades. And to this day many Mexicans are loath to endorse the final conclusion of a six-year government investigation: That the confessed assassin, a 24-year-old maquiladora worker named Mario Aburto, acted alone.

Colosio’s killing was an event unseen in Mexico since the 1928 assassination of President Alvaro Obregón. As the candidate of Mexico’s long-ruling Institutional Revolutionary Party, the PRI, the 44-year-old native of Magdalena de Kino, Sonora, was widely assumed to be the country’s next president.

In Lomas Taurinas, Carmen Robles recalls the people who rushed past her in panic that Wednesday afternoon. Twenty years later, the 47-year-old clothing vendor harbors no doubt about Colosio’s killing: “It was definitely a conspiracy.”

Six years and three months after Colosio’s visit, the PRI lost its 71-year grip on Mexico’s presidency with the election of Vicente Fox of Mexico’s National Action Party, the PAN. To some, Colosio’s murder helped accelerate change that was already underway, one of a series of events that year that had a transformative effect on Mexico and whose effects linger today.

Luis Donaldo Colosio, presidential candidate of Mexico's ruling party, is helped by aides after being shot during a campaign rally in the Colonia Lomas Taurinas section of Tijuana. Colosio died 2 1/2 hours later.Robert Gauthier — UT San Diego

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Luis Donaldo Colosio, presidential candidate of Mexico's ruling party, is helped by aides after being shot during a campaign rally in the Colonia Lomas Taurinas section of Tijuana. Colosio died 2 1/2 hours later.
/ UT San Diego

The passage of time has done little to quell public interest in a case that generates comparisons with the November 1963 assassination of President John F. Kennedy. This month, television programs, radio interviews, newspaper articles, across Mexico are reviving discussion about the March 23, 1994, magnicidio, or assassination, that drew the world’s attention to Lomas Taurinas.

“One of most tragic days in contemporary Mexican history,” Mexican President Enrique Peña Nieto wrote last week in an essay.

Mexico is a vastly different country than it was 20 years ago, more globalized economically, more politically plural, but still struggling to emerge from its past, and the anniversary of Colosio’s killing forces a look back.

Othon Cortez is pictured in a plaza where a monument is dedicated to Luis Donaldo Colosio, the slain Mexican presidential candidate. Cortez was was accused of being the second gunman in the Colosio assassination, and then absolved.David Maung

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Othon Cortez is pictured in a plaza where a monument is dedicated to Luis Donaldo Colosio, the slain Mexican presidential candidate. Cortez was was accused of being the second gunman in the Colosio assassination, and then absolved.

“It remains a political mystery to this day,” said political analyst Joyce Langston of the Center of Research and Teaching in Economics, a think tank in Mexico City.

Mexicans doubt the lone gunman theory, “for the same reason it’s difficult to accept that for no good reason some crazy guy killed Kennedy,” she said. “Even if Aburto actually killed him, many people think that it was a political hit, many people in the political elite somehow believe without evidence it was a political conspiracy against Colosio.”

A former president of the PRI who had served as Mexico’s secretary for social development, Colosio was President Carlos Salinas de Gortari’s hand-picked successor, a man some hoped could bridge the gap between the party’s traditionalists and the neo-liberals pushing for economic growth.

Days before his appearance in Lomas Taurinas, Colosio had drawn attention with a speech in Mexico City: “I see a Mexico with hunger and thirst for justice,” he said, words still repeated by those who believe Colosio would have made a difference in Mexico.

Conspiracy theorists offer a range of possibilities as to who might have been behind the candidate’s killing, from corrupt and hard-line PRIistas resentful of Mexico’s moves toward economic modernization, to political rivals, to drug traffickers and the politicians who protected them.

“The only thing that makes sense to me, in my own head, is that this was an internal dispute inside the PRI,” said Ernesto Ruffo, a PAN member who was governor of Baja California at the time of Colosio’s visit. Aburto “is a person who physically carried out the killing,” Ruffo said, but “everybody believes that it was power struggle.”

Colosio’s death helped weaken an already divided party, and hastened a process of political change in Mexico, said Ruffo, currently a federal senator from Baja California. Ernesto Zedillo replaced Colosio as the PRI’s candidate and won the July 2 election, but the party lost its 71-year grip on the presidency in 2000 with the election of PAN member Vicente Fox.

Scholars such as Langston say Colosio’s killing cannot be taken in isolation, but was one of a series of events that jolted Mexico in 1994 — including the armed Zapatista rebellion in Chiapas on Jan. 1, the same day that the North American Free Trade Agreement was launched. In September of that year, José Francisco Ruiz Massieu, the PRI’s national leader was assassinated, and in December, a peso devaluation forced an economic crisis.

Two decades after Colosio’s death, “I think the trauma and the sense of crisis lingers,” said Michael Lettieri, a visiting scholar at UC San Diego’s Center for U.S.-Mexican Studies. The events of 1994, “changed the way people looked at the political system,” he said. “Did it change the course of history? I’m not sure, but it’s had a lingering effect on the political psyche.”

Lomas Taurinas today is a neighborhood like so many others in Tijuana that sprang up without government planning. Its tightly packed, self-built houses cling to steep hillsides, with brightly colored flowers spilling over crudely made fences. Dogs bark, and vendors drive their trucks through its meandering streets, loudspeakers blaring their wares — from tanks of gas to jugs of water to tamales.

What sets it apart is the statue of Colosio that rises over a small plaza that is the site of yearly ceremonies commemorating the candidate’s death.

Besides the memorial service in Lomas Taurinas this afternoon, the PRI is also planning a five-kilometer foot race in Colosio’s honor this morning that will start off from the PRI’s headquarters near the U.S. border.

Antonio Cano, who was president of the PRI in Tijuana at the time of killing, plans his own quiet homage to Colosio today, far from any crowds. Cano was with Colosio in Lomas Taurinas on the day of his death, “and I saw nothing that would make me think there was a conspiracy,” he said. “We have all have a right to doubts, but reality tells me there was a single assassin.”

Cano recalled that on the day of the rally, Colosio “was very happy, and had this attitude that he wanted to have a different kind of campaign, and didn’t want to be ostentatious with his security apparatus. Colosio “always asked to be close to the people,” Cano said.

Though Baja California was governed by the PAN at the time of Colosio’s visit, Lomas Taurinas had remained staunchly PRIsta, said Agustín Pérez Rivera, the community’s founder.

Several thousand people gathered on a dirt lot greeted Colosio’s arrival that day, Rivera recalled. Colosio spoke from the bed of a truck, then stepped down and made his way through the crush of supporters as the bouncy song “La Culebra” blared from the loudspeakers.

A video of the event shows a hand from the crowd placing a gun at Colosio’s temple. As he falls, a second shot is fired, hitting him in the abdomen.

Minutes later, photographs show a bloodied Aburto being taken away. But soon after, the investigation led to other arrests, including those of Vicente and Rodolfo Mayoral, a father and son who were part of an unarmed crowd-control force, as well as Tranquilino Sanchez. All three were accused of blocking the path of Colosio’s bodyguards, but eventually released for lack of evidence.

Also at the rally was Othon Cortéz Vásquez, a driver for the PRI who was standing near Colosio at the time he was shot. Eleven months after Colosio’s slaying, he was accused of firing the second shot. Cortéz said he was tortured during 18 months in Mexico’s high-security Almoloya prison, and was eventually released for lack of evidence.

Cortéz filed suit against his government accusers — Attorney General Antonio Lozano Gracica, and the special prosecutor, Pablo Chapa Bezanilla — demanding a half-million dollars in compensation. “I see them as cockroaches, the worst that Mexico has,” Cortéz said in an interview this week. But they counter-sued, alleging defamation, and a court ordered Cortéz to pay more than $1.35 million in damages.

Cortéz he is now petitioning President Peña Nieto to vacate the fine, and come through with some compensation. “They practically ruined my life,” said Cortéz, glad for his job as a security guard at a city park. “But I am grateful, because in spite of suffering, we are able to move forward.”

He won’t speculate about who could have been behind Colosio’s killing.